State mining company Solid Energy says using Southland's large coal reserves would reduce, not worsen, global greenhouse gas emissions.
The company devoted some time at its Annual Meeting on Thursday defending its lignite plans.
Solid Energy wants to develop three billion tonnes of lignite under farms in Eastern Southland into briquettes, fertiliser and diesel.
Climate change activist Tim Jones suggested billions of tonnes of carbon dioxide would be released, and would be likely to speed up global climate change.
But the company's chief executive, Don Elder, maintained the projects would reduce global emissions because New Zealand coal products would use the latest technology to be less polluting.